Egg testing method and machine



4 Sheets-Sheet l F. L. RIVENBURGH Filed June 3, 1936 EGG TESTING METHODAND MACHINE @www .www

March 7, 1939.

Il. 0 nu NEEN Marc-h 7, 1939.

` F. L. RIVENBURGH EGG TESTING METHOD AND MACHINE 4 Sheets-sheet 2 FiledJune', 1936 March 7, 1939. F. l.. RIVENBURGH l 2,149,686

AEGG TESTING METHOD AND MACHINE Filed June' 5, 1956 4 sheets-sheer 3March 7, 1939. F. L. RIVENBURGH EGG TESTING METHOD AND MACHINE 4Sheets-Sheet 4 Filed June 3, 19.36

Patented Mar. 7, 1939 UNITED STATES lPATENT OFFICE EGG TESTING METnoDAND MACHINE Frederick L. Bfivcnburgh, Sprlngiield, Ohio Application Junes, 193s, serial No. sacas 23 claims. (ci. 209-81) f within the apparatusfor sorting the eggs into groups in accordance with the determination ythus allorded. One of the features of the present invention consists inthe provision of an apparatus for successively preparing and advancingthe eggs for testing, means for testing the eggs, and devices responsiveto the indication a test for sorting the eggs into groups.

Another feature is the provision of a method and apparatus for locallyreducing the electrical resistance between points of the egg which arelat different levels of height by substantiallyeliminating the electricalresistance of the egg shell thereat.v y

Another feature of the present invention is the provision' of means foradvancing the eggs through a pre-treating zone in which they arerendered more capable of responseduring testing, a testing zone, and asorting zone; together with the provision of means for testing the eggand determining the selection accomplished in the sorting zone.

A further feature of the present invention is the provision ofsynchronized means for conveying the eggs successively through apre-treating zone, a testing zone, and a sorting zone, along withdevices operated in the several zones, the regularity of advancement ofthe eggs being employed for assuring the existenceof standard conditionsduring the testing.

Still another feature of the present invention is the provision of ameans for conveying the eggs, devices for prewetting the egg shellbefore testing, testing electrodes associated with electrical circuitmeans for giving an amplified response, and sorting means energized whenthe response of a particular egg is of'a given characteristic andserving to prepare for the sorting of the egg when this egg arrives in aselecting zone.

A further feature of the present invention is the provision of an eggtesting apparatus whichv is responsive to the potential differenceexsiting in eggs of character acceptable for hatching, for example, orfor other purposes.

Another feature of the present invention is the provision of a method oftesting eggs with respect to hatchability by determining the potentialdifference inherent in the eggs undergoing test.

A further feature of the invention is the provision of a method of,testing by reducing the resistance of the egg shell and membrane to thepassage of current therethrough, and then determining the potentialdierence inherent in the egg.

Still another feature of the present invention is the provision of amethod of testing eggs by determining the relative positive or negativepolarity existing, by reason of the inherent potential difference,between' the top and bottom of an egg of hatchable nature.

Still another feature of the present invention is the provision of anapparatus and a method for testing eggs by which the eggs are maintainedin a horizontal position and against rotation about a horizontal axisfor a predetermined time, are subjected to a pre-wetting treatment atlocalized portions of their tops and bottoms for a predetermined time,are tested for inherent potential diierences between said localizedwetted areas, and then are selected in accordance with the potentialdiierences so dietermined.

Other features of the invention reside in particular details ofconstruction and arrangement of the several parts and in theircombinations and operation, as will be set out in the course of thefollowing specication and claims.

An illustrative form of practicing the invention is shown on theaccompanying drawings, in

which:

Figure l is a plan view of the mechanism, and indicates an associatedelectrical circuit diagrammatically.

'Figure 2 is a side elevation of the machine, partly in section.

Figure 3 is a iragmental elevation partly in section, on an enlargedscale', of the pre-selector drum and the egg-discharging mechanism.

Figures 4 and 5 are respectively, on an enla tion of the conveyor beltwith its apertures and pins.

Figure 11 is a detail substantially on line l I-i i of Fig. 8.

In these drawings, the apparatus is illustrated as having the supportinglegs i@ for a frame consisting of the two longitudinal sills Il and thetwo end sills i2 which-4 are connected rigidly together for supportingother parts of the mechanism. VRising from the longitudinal sills Il arethe angular pieces I3 providing legs for supporting the upper rails Mwhich provide spaced supporting guides for an upper ight of the conveyorbelt.

A main driving pulley P is fixed on a transverse shaft I1 mounted by4bearings I8 on the side sills and having a worm I9 engaged with theAworm wheel 20 of the lengthwise extending main shaft 2| which issupported by the hangers 22.

A drum shaft 23 at the feeding end of the apparatus is mounted onbearings 24 and supports a feeding drum 25. Adjacent the discharge endof the machine is a second drum shaft 26 mounted on bearings 21 andhaving a ratchet 28 xed thereto, outside of the frame in thisillustrated form; and also having a second drum 28 secured thereto, sothat the drum may be turned as the ratchet 28 is advanced.

'Ihe drums 25 and 28 receive a conveyor belt CB which is shown in Fig.10 to have a plurality of apertures 33 which are oval in shape and aresmaller than the eggs to be tested but provide an adequate supportagainst rolling of the eggs. The eggs extend downwardly below the lowersurface of the belt CB. Between each two apertures on the belt CB isprovided a pair ofA transversely spaced pins 35 which prevent rotationof the egg about a vertical axis and rolling of the egg along the lengthof the belt'. These pins 35 preferably 'have collars 35a (Fig. 10) abovethe belt, and have nuts 35h engaging threaded ends at the inner sideof'the conveyor belt (Fig. 3) for reception in corresponding cavities inthe drums 25 and 29.

The eggs may be introduced to the apparatus by movement along a guidechannel 36 from which the eggs are lifted by the pairs of pins 35 andthus brought to the top of the drum 25 so that the eggs are received inthe holes 33. These pins cooperate with the body of the belt CB and pickup the eggs from the inlet guide channel 36, and center them withrespect to the holes 33 in the conveyor belt; and likewise operate forguiding the eggs falling along the belt near the hood 80, and to centerthem for proper release at the outlet channel 8|.

The belt passes successively through a pre- A treating zone, a testingzone, and a. selecting zone.

Since' the eggs naturally have a high resistance, it is desirable todecrease this resistance as much as possible without injury to thevitality of the egg, before testing the egg. In the form shown in Figs.1 and 2, this is accomplished by the Autilization of wetting structuresWS, of which four are shown. 'Ihe testing system comprises a pair ofelectrodes which are presented at the top and the bottom of the egg bytesting structure TS, of which one is shown on the drawings. Theselecting zone is comprised upon and around the second drum 29, and willbe described more in detail hereinafter. Between the testing and thedelivering of the eggs to the exit channels, it is preferred to includealso acleaning structure CS for removing superficial treating solutionfrom the egg shells.

The structures WS, TS and CS comprise actuating mechanisms which aresubstantially identical in design, and are each driven from the mainlongitudinal shaft 2| so that proper synchronism is observed between themovements of the belt and eggs and the operations of these structures.As shown in Eig. 6, these structures comprise the supporting columns 40secured to the rear longitudinal sill member and provided with two pairsof parallel-motion links 4|, 42 which are joined at their outer ends bythe holders 43. Each of these holders for the struced on the shaft 2|.

tures WS and TS supports an assembly for the regulated delivery ofwetting solution to the surface of the egg shell, comprising the outercasing structure 44, a porous application wick 45, and an end 48connected to the supply conduit 41. 'Ihe two pairs of parallel-'motionlinks are connected by a spring 48 having a tension adjusting member 48.The adjacent links in the two pairs are provided with supports 50 forthe rollers 5| which cooperate with the cam pieces 52 mount- These camsare symmetrical, that is, they have two humps which operatesimultaneously upon the upper and lower rollers 5| so that the holders43 are moved toward and away from one another in unison.

The structure CS resembles that set out in Fig. 6 with respect to theactuating parts, but its conduit 41a is connected (Fig. 1) to a conduit81h leading to a vacuum pump.

For the purpose of closing a switch in the selector circuit, as will bedescribed hereinafter, a switch structure 55 is mounted on one post 40to be actuated by the cam 52 each time that the shaft 2| causes allholders 43 to be brought toward one another for contacting the eggslocated therebetween.

As shown in Figs. 1, 4 and 5, the shaft 2| also has a further cam 60fixed thereon for engaging a roller 5| mounted on a rock arm 62pivotally supported on the adjacent hanger 22. It will be noted that thecam 58 has two humps, so that it produces two reciprocations of the rockarm 52 for each revolution of the shaft 2|, these movements being timedso that they occur during the periods at which the wider humps of cams52 are operating to maintain the holders i3 separated; and thus noobstruction is aorded by the parts supported thereby to the advancingmovement of the eggs on the conveyor belt CB. The arm 52 is connected bya link 63 of adjustable length with the end of-a rock arm Ed which isloosely mounted on the end of the shaft 26:

- it is preferred to form this rock arm 84 to engage both the inner faceand also the outer hub of the ratchet 28, so that this ratchet serves tomaintain the arm in proper operating position. The rock arm 86 supportsa pawl 65 which is engaged with the teeth of the ratchet wheel 28. Inoperation, the rock arm 6d moves the pawl 65 back and forth once forevery half revolution of the shaft 2|, and thus produces a rocking ofthe ratchet 28 once for each half revolution of the shaft 2|, andtherefore once for each approach and receding movement of the holders43.

It will be noted that the ratchet 28 is illustratively shown withsixteen teeth, so that eight revolutions of the shaft 2| are requiredfor one revolutionV of the shaft 26.

'Ihe drum 29 has sixteen equally spaced apertures on its front face(Fig. 2), each of which re- -ceives a pin (Fig. 8) having a body 'I8guided in the aperture, an inner end flange 1| to prevent the movementof the pin through the aperture, and a. reduced outer end 'l2 providinga shoulder. Inside the drum 29 is provided a plurality of leaf springs13 each cooperating with one of the pins 10 for pressing it normallyoutward. Each pin is provided with a locking device comprising the rocklever 18 having a. notched arm which normally rests against the shoulderof the pin T0 and is limited against a further relative clockwisemovement (Fig. 3) by engaging the reduced portion 12 of the pin. 'Thistendency toward clockwise movement is produced by the individual springs'I5 which connect an end of the rock lever 15 with a: fixed point on theouter face of the drum 295. The other arms of the rock levers are mentof the rock lever about its pivot 14a on the drum 29, so that thenotched end passes from above the shoulder of pin 1li; and this pin isthen projected outwardly -by the leaf spring 13. The engagement of the.larger portion of the pin -10 with the rock lever 14 prevents thereturn of the latter to the former position.

As there are sixteen teeth on the ratchet 2B, sixteen pins 10 withcorresponding rock levers 14 are provided on the drum 29; and in likemanner, sixteen egg holders of the belt CB are moved past aigiven pointfor each revolution of the drum 29.

At the discharge end, the drum 29 is surrounded by a hood having checkwalls to prevent lateral displacement of the .eggs from between thepairs of pins, and a semicircular peripheral wall which is of slightlylarger radius than the radius swept by the pins 35, so that these pinsmay move freely within the hood 80, but so that the eggs.1 aremaintained between the pairs of pins during this travel. Just below thehorizontal plane of the axis of shaft 26, a discharge channel 8l isfastened beneath the end sill i2. Upwardly from the surface of thedischarge channel 8i the hood 80 is provided with an orifice in itsperipheral wall through which an egg may roll from the pair of pins 35,when these are positioned in substantial alignment With the dischargechannel 8 I, and thus downward along the channel 8|. Such is the normaldischarge for eggs which have been found of proper quality for hatchingpurposes, ,for example. This orifice may be A bracket arm 83, xed to therail il supports the pivot 84 of a selecting rock lever 85 which has onecam-like end 85a positioned in the path of such of the pins 1l) as havebeen moved to the outermost position. This rock lever 85 has a returnspring 86' for normally holding it in the dotted line position of Fig.1l. Thus when a pin 10 is in the outermost or actuated position, itencounters the lever 85. and causes the same to rock in acounterclockwise direction (Fig. 11) until it latches the door 82against `opening 'by the pressure of an egg, so that the correspondingegg cannot leave the pins 35 and move down the discharge channel 8l, butis retained within the hood 80 and finally is carried to a point beneaththe axis of shaft 26, and thenls permitted to move downward along asecond discharge channel 38.

At an angular position corresponding to the position of the pins 35 fromalignment with the discharge channel 8i, the hood 80 is providedinternally with a wedging or cam piece 89 which engages with the end ofthe reduced portion of each pin 10 which has been moved to its outwardposition and operates to depress or move such a pin inwardly until itsshoulder is removed from the path of movement of the notched end of thecorresponding rock lever 14, whereupon this rock lever is moved inwardlyby its spring 15; and the pre-selector storage device thus constitutedis restored to its closed by a door-82.

which have just passed.

former position'ready for a fresh operation when this particularassemblage arrives opposite the core or plunger 16 of the solenoid 11,if the egg then under test is likewise to be selected for. move- .mentinto the discharge conveyor B8 rather than into the discharge conveyor8l.

The electrode for the testing structure TS (Fig. 7) is lpreferablyformed with its jacket 44 of insulating material, such as glass,condensate resin, etc. At the end adjacent the egg, this jacket is openand receives aporous body 45 through which the electrolyte solution isconducted to the surface of the egg. This electrode jacket is supportedvon the corresponding holder 43 by the straps 43a. The electrodestructure includes the electrode plate |01 located within thejacket 44and joined by an insulated and shielded conductor |02 to the electricalapparatus, as described hereinafter. The upper and lower electrodes arepreferably formed identical,

the inner end of the body 45 being tapered or inclined so that airbubbles in the lower electrode may not prevent the movement of liquid'to the egg-engaged surface of the body 45 or prevent the proper flow ofcurrent. It-is preferred to form the body 45 of felting and likematerial; and care should be taken to provide, however, an electricallyneutral felting for this service, as

. either alkaline or acid reaction of the felting gives rise to certainaccidental currents which raise certain dilculties of compensation,particularly as either acid or alkaline feltings are apt to benon-uniform in respect to one another.

The construction of the devices used in the holders 43 for thepre-wetting structures WS may be identical with the devices used aselectrodes, although it is not necessary to provide the actual electrodeplates Illi therein. Similarly, the cleaning structures CS may havedevices of similar nature, care being taken to avoid penetration of airinto the body 45 at points above the actual surface engaged with theegg, insofar as feasible.

The various pre-wetting structures WS are connected together sothattheir upper and lower jackets 44 receive a pre-wetting solution. Itis preferred that this pre-wetting solution should be identical inchemical constitution with the solution which is being employed at thetesting structure TS. Where silver chloride electrodes are employed, a7percent calcium chloride solution has been found to give excellentresults. It will be noted that these pre-wetting structures WS areutilizedv for moistening the upper and lower surfaces of the eggs,without depositing such great quantitiesl of solution thereon `thattrickling may occur downwardly along the egg shell surface to establisha short circuiting betweenthe top and bottom wetted areas. Since noelectrical conductivity is involved in the prewetting zone, all of thesejackets 44 may be connected by their conduits 61 with a single reservoir95. The upper and lower electrodes in the testing structure TS, however,must be maintained insulated from one another so far as feasible; andfor this purpose separatetanks 96 and 91 of glass or the like areconnected to the lower electrode plate ||b is connected by a con-vductor |02b with the ground and with the central point of a pair of gridcontrolling resistances |08a, |0811. The conductor |08 leads from theintermediate point of the potentiometer |01 to the other end of the gridcontrol resistance |00a, and to the grid of a vacuum tube VT| of thescreen-grid type. The other vterminal of grid control resistance |08b isconnected to the control grid of the screen-grid vacuum tube VT2. Thefilaments of the tubes VTI and V'12 are connected together and suppliedfrom a filament battery I0 through a control switch A conductorcontaining a grid biasing battery ||3 is joined to the conductor |02b sothat the grid current can be eliminated. The screen grids of the vacuumtubes VTI and VT2 are connected by the conductor H4 which extends to thenegative terminal of the anode battery H5, the positive terminal of thescreen grid biasing battery H6,

and thence to the ground. The positive terminal of the anode battery ||5is connected to the switch ||1 with an intermediate point of theadjusting or balancing resistance ||8. One end of this adjustingresistance is connected by a conductor Illia and an anode circuitresistance |20awith the anode, of the-vacuum tube VT|while the otherterminal of the balancing resistance ||8 is connected similarly by aconductor ||9b and resistance |20b with the anode of the other vacuumtube VT2. 'I'hese vacuum tubes VT| and VT2 are connected togetherl inso-called push-pull bridge balance arrangement for direct currentamplification.

The response of the amplifying system, therefore, is to change thepotential drop between the two anodes. The anode of vacuum tube VT| isconnected by a conductor |2|a with the grid of a power amplifier VT3,while the anode of vacuum tube VT2 is connected by a conductor |2|b withthe cathode of the tube VT3. Owing to the sensitivity required anddifiiculties arising from stray currents, it is preferred to constructthe initial or push-,pull amplifier for actuating by current ofrigorously maintained potential, as by using batteries forthe filament,anode, control grid and screen grid circuits. Such can also be used forthe power amplifier tube VT3; but since this tube is in eilectmultiplying the response of the rst stage of amplification, it ispossible to employ circuits so that this tube is operated from the usualalternating current supply means in the illustrated form. For thispurpose the filament circuit conductors |23 lead to a transformerwinding |23a, as' usual. The, anode of the power amplifier tube VT3 isconnected by a conductor |24 with one terminal of the ammeter MA and.one terminal of the coil of a relay MR, with the meter-control switch|26, and with a resistance |3017. 'Ihis conductor |24 also is connectedin multiple with a plurality of shunting resistors |21 of differentresistances which are selected by a switch |28, this switch in turnbeing connected by a conductor |20 with supply for anode current.

MA and the coil of relay MR.. The conductor r |20a has a branchincluding in series a resistance |30 which operates for balancing themeter; and conductor |29b has a similar branch including a resistance30a for balancing the relay coil; the conductor |29 is also connectedthrough switch |26 with conductor |283; and thus with the Thecompensating battery |3| is 'connected between the compensatorresistance |301) and the conductor |29. A conventional type of filter,comprising capacities |34 and chokes |35, is associated with a winding|33 of the power transformer for supplying conductors |2|a, |2|b withthe necessary anode current for the vacuum tube VT3.

The normally closed contact points in the relay MR govern a circuitcomprising a conductor |3| connected to the solenoid 11, a conductor |38leading to a winding |39 of the power transformer, a conductor |40leading from the contacts to the switch 55 (Fig. 6), and a conductor |4|leading from this switch to the solenoid 11.

The power transformer, comprising the windings 23a, |33 and |39, issupplied from the current mains |45 through a switch |46. It ispreferred to mount the switches ||1, |26 and |46 on a single shaft, sothat they may be turned on and off together.

For the purpose of Calibrating the equipment, a branch |50 extends fromthe conductor |02b to a common point of two resistances |52. Theresistance i 5| is connected to a standardizing battery |53, and thisbattery in turn is connected .with a terminal |56 of adouble-pole'switch |55.

[The switch blade corresponding to terminal |54 forthis other switchblade is connected to conductor |02a. The ratio of the resistances |5|,|5215 preferably selected such that the potential between conductors |50and |02a is a decimal fraction of the normal potential delivered by thebattery |53 and' of the same order of value as the normal potential ofan acceptable egg. Since this battery is employed only from time to timefor standardizing, the drain upon it is low and its life is long. Inparticular, it is thus possible to employ commercial batteries for thegeneral standardization equipment without requiring expensivestandard-cell set-ups.

It is preferred to provide the apparatus with counting and markingdevices for controlling the operation of the machine and the product.For this purpose the rst counting mechanism IC is provided upon a post|3b rising from a longitudinal sill cludes a rockable actuating arm |20which is positioned between the path of movement of the pairs of pins 35so that it is contacted by the eggs as they pass forward with theconveyor belt CB, and hence this counter IC is actuated each time an eggpasses beneath the nger |20. Similarly, a counter mechanism RC ismounted on the longitudinal sill adjacent the solenoid 11, and

is actuated by the plunger 16 thereof (Fig. 3) each This countingmechanism inthe selected eggs to designate the fact and date ofselection, and is effective upon the eggs as the latter roll downward inthe channel 8| over the surface of this pad ,The biological orincubation activity of fertile' `eggs is present at room temperature(7G-80 degrees FJ, but it is very much greater at the optimum incubationtemperature (around 100 .degrees FJ. The electrical potential differenceobserved on the eggs is intimately connected with the metabolism andgrowth of the embryos.-

.While itis possible to test the eggs immediately after laying, or afterthey have been cooled to room temperature, it is usually preferable toaccomplish a short period of heating before making the test in order toeect a relative increase of the potential dierence by the initialactivity of the embryo in a fertile wg. The tem. perature to which theembryo is heated is preferably around the optimum incubation temperavture, and should not exceed 110 degrees F. It will be understood,however, that an egg may be subjected to a lhigher external condition ofheating in order to bring it to the desired temperature rapidly. Thisperiod, however, is preferably so short that no visible growth of aweaklyfertile egg has occurred, or that aging or decomthe embryo to fulldevelopment and results in the production of a strong sturdy chick. Adead egg is one which has been fertile to some degree but whose normalcapability of cell division has ceased. A "sterle egg is one which hasab initio not been fertile.

Tests made after 3,to 6 hours of heating have been found to giveexcellent results, and highly satisfactory results have been obtainedafter 1%/2 hours of heating. It is preferred to heat for at least onehour. (The period of heating is f calculated from the moment that theeggs,-be-

ing at room temperature, are placed in the heating cabinet.) When theeggs are tested directly at room temperature, the electricalmeasurements -are generally lower, and a certain proportion of thefertile eggs apparently give very little or no response. vThis increaseof electrical effects arising from the very short heating periods may bereferred to as having the effect of "arousing" the eggs; and it ispreferred that the measurements should be made at the optimumtemperature for producing this effect without danger of interruption orderangement of the usual cell division which'constitutes growth of theembryo.

The germ within the egg is surrounded by various membranes andmaterials, and tends automatically to assume a definitelyv orientedposition and to becorfe located adjacent the top of the egg when the eggis left lying on its side. The time required for this varies slightlywith the stage of development o! the and usually is around 10 seconds.Hence in testing eggs it is desirable to have each egg remain quiescentin a particular horizontal position for a period of time at leastsuiiicient for the germ to adjust itself. This position is likewisecharacteristic in that the maximum potential difierence develops whenthis position is maintained. For example, when an egg has beenincubatedfor 2 to 3 days, the top electrode will be at 10 to 20millivoltsiiegative potential, relative to the bottom electrode. If theeggis turned upsidedown and immediately tested, the upper electrode ispositive with respect to the bottom electrode until the germ hasoriented itself by rotation and/or displacement and returned to normal,and then the-top electrode will again indicate a relative to 20millivolt negative potential with respect to the bottom electrode. whichmay be regarded as a predetermined standard of electromotive force whichis demonstrated by hatchable eggs of this history. Similarly,determinations of standards for groups of eggs of differing history maybe established.

As instances of the potential diierences which i have been observed intesting eggs, the following Ymay be noted: Table After the seventh day,the ability of the germ to orient itself is gradually lost and thepotential diierence depends upon the position of the embryo between theelectrodes; its marmnm value is around 50 millivolts.

Sometimes the reversal of an egg does not produce the immediate reversalof relative potential at the electrodes, followed by -the slow recoveryto the former condition. One cause of rthisris that the embryo issticking to the shell. In this case, the measurementmay indicate thatthe egggis sterile when s uch is not the case. However, this-indicationmeans that the egg will not be employed for hatching-a desirable type ofselectionas the embryo of such eggs generally die in the shell.

The dry shell and underlying membrane of an egg-is practically aninsulator as the resistance is usually greater thanrlO megohms. Hencethe preparatory treatment of the egg prior to test hasfbeen devised toinclude preferably a wetting with a solution in order to reduce theresistance.

As an alternative for such prewetting, electrodes of material such assilver or platinum-iridium, and having a diameter of, say, oneten-thousandth of an' inch for a length of one thirty-second of aninchmay be caused to penetrate the egg shell, and to contact through theshell membrances; this does not have an injurious effect upon the embryoor cause cracking of the shell when due precautions as to size,pressures, etc., are observed: in such cases, no prewetting oraftercleaning is necessary. Since present vacuum tubes tend to beunstable unless a closed external grid-cathode path. is provided with aresistance of the same order as the internal resistance of this path,and since such a constantly-closed path would be in shunt of the paththrough the egg and hence will carry a part of the current eiiectsderived from the egg, it is usually necessary to reduce the effectiveresistance between the wetted spots at the Atop and bottom of the eggshell to a value less than.500,000 ohms .n order toavoid too expensivelosses and to permit stable operation of the amplifier system. It hasbeen 4found that wetting the surfaces of the eggs in spots at top andbottom which are about 3A of an inch in diameter each, is sufiicient toeffect a diminution of the resistance which drops gradually until itmay, reachr a value of 500,000 to 100,000 ohms: in some instances it canbe reduced to as low as 30,000 ohms by appropriate handling. 'I'heaction of the devices 45 in the wetting structures is to apply a slightfrictional rubbing or mechanical agitation which is 4advantageous ineffecting a quick penetration of the solution into the egg shell. Thetime required for the penetration of this solution varies by reason ofseveral factors, but it has been found that 1 to 2 minutes is suflicientin practically all instances to permit comparisons of groups of eggswhich do not have unusual shell formations, or an unusual deposit ofextraneous material, for example. It is necessary to prevent the currentfrom running around the egg from the top spot to the bottom spot, or

to any grounded portion of the structure. This' is avoided by having theconveyor belt of insulating material, and by having the felts of suchabsorption properties and supplied by liquid under a suflicient head tocause the moistening of the surfaces of the felt which encounter the eggshell without actual dripping or excess saturation thereof. It may bepointed out that the presence of the relatively narrow wetted stripbetween the top and bottom spots will have a much less resistance thanthat of the path through the shell, the various membranes, and the germstructures, or than that of the external circuit. By way of comparisonit may be pointed out that the resistance between two properly wettedspots and the potential difference created 'thereat by the egg issubstantially the same as the resistance and potential differencedetermined by removing portions of the egg shell 'and testing thecontents directly.

The electrodes and electrolyte solution, and hence the pre-wettingsolutions, should not contain materials which may be introduced throughthe egg shells and act as a poison upon the egg.

It is preferred to employ non-polarizable or reversible electrodes, suchas silver-silver chloride electrodes: platinum electrodes have been usedsuccessfully. The electrolyte for such electrodes may comprise solutionsof calcium, sodium or potassium chlorides individually or in mixture. Inan actual structure, the electrodes were formed by using a thin sheet ofsilver having a surface of about V2 a square inch located in a glasstube 44 one inch in diameter and six inches long. 'I'he tube was filledwith a chloride solution, another piece of silver brought into contactwith the solution, and current passed under a pressure of 3 volts forabout 10 minutes,4 with the electrode connected to the positive pole inorder to coat the electrodes with silver chloride.

It `is preferred to employ calcium chloride in concentrations from 3 to10 percent, preferably around 7 percent, for the particular arrangementof circuit and other parts shown on the drawings. The solutionpreferably has a pH around '1.2. A more acid solution appears definitelyunfavorable, but a slight alkalinity may be tolerated.

The machine may be operated as follows:

The switches ||1, |26 and |46 are closed by operating the knob Sw. Thevacuum tubes are permitted to warm up for a suiiicient time toassurestability in normal operation.

` The circuits may be checked for balance and continuity by placing theselector switch |28 for connecting the shunt f 21 of lowest resistancein parallel with the :rwter MA; and switch |25 is l this meter ofgalvanometer type and to adjust it so thatthe zero on the scalerepresents the normal open-circuit condition of the parts. Thesensitivity of the meter can be varied by resistance |30, while thepotentiometer I I8 is varied to bring the reading back to zero. Theswitch |03 is then closed in either direction. With the electrodestructures in contact and saturated with the normal wetting liquid, themeter MA should remain at zero if there is no contact difference ofpotential between the electrode plates ||a, |0|b. Any change of readingof the meter can now be compensated by movement of the potentiometer|01, possibly with a reversal of the compensating voltage, by changingthe switch |03. When this primary adjustment has been accomplished, theelectrode structures are separated again and a final adjustment obtainedby moving the switch |28 to a contact representing a higher resistancein shunt of the meter MA; and this meter is then balanced and electrodepotentials corrected as before. This can be repeated successivelyaccording to the number of shunt esistors |21 employed, so thatultimately a very fine adjustment of balance is attained.

It is now desirable to standardize the device. This is done by closingthe switch |55 and noting the reading at the meter MA. Since the battery`A|53 gives a substantially constant potential, the

readings of the m'eter should be uniform from day to day when ths testis being made.

The switch |25 is now shifted so that the output current of the tube VT3flows through the relay MR. The standardizing current should now operateto energize the relay and move its armature. The sensitivity of thisrelay may be adjusted by the resistance |30a, so that the relay willjust close with the preselected standardizing potential differencebetween terminal |54 and conductor |50, this potential difference beingselected to correspond with the potential differences existing in eggswhich are good for hatching, as distinguished from lower potentialdifferences of eggs which are bad for hatching. This particularpotential difference will vary, as set out herein, according to thelength of time and the conditions under which the eggs have beenundergoing incubation or other preliminary operations for arousing them.

The reservoirs 95, 96 and 91 are filled with the' desired wettingsolution, Aand the vacuum pump connected to conduit 41h is started. Themain pulley P is set in rotation.

The shaft 2| is driven and the wetting structures, testing structuresand cleaning structures are caused to move toward and recede from oneanother twice for each revolution of the shaft 2|. It is preferred thatthe lower elementsv of each structure should slightly raise the egg awayfrom the conveyor belt CB at each operation, to assure a positivecontact of the wetting wick 45 with the bottom of the egg under slightpre.' "1re, at the same time that the upper wick 45 errounters the topof the egg. Hence there is a slight frictional or rubbing eiect appliedto the egg at the tme that the saturated wick is brought in contacttherewitha condition favorable for the penetration of the wettingsolution through the shell of the egg. The cam 60 also effects themovement of the ratchet 28 and shaft 26 so that the conveyor belt CBisvmoved forward by steps, one

step being produced following each movement of the wetting, testing andcleaning structures.

Eggs are now inserted in the supply trough 36 and permitted to feeddownward until they are engaged and lifted by the pairs of pins 35 ofthe conveyor belt CB at each forward stepping movement of the conveyorbelt past this feeding station. These eggs are therefore moved beneaththe finger 200 of the counter IC, and are counted to show the totalnumber of eggs tested by the machine. The eggs then successivelyencounter the wetting structure WS'and are detained on the conveyor beltCB as it makes its stepwise movement'until they have been sumcientlysaturated for spots at top and bottom to overcome the initial highresistance of the egg shell. The eggs then move to the testing stationTS.

As the egg is brought to a standstill at the testing station TS and theelectrode structures are brought down and up into contact with it, thecam 52 causes a closure of the switch 55.

The contact of the electrode structures with the wet spots at top andbottom of the egg -permits the inherent potential of the egg to mani-.

fest itself by potential difference between conductors |02a, |021), thispotential difference being superimposed upon a correcting orcompensating potential difference introduced at potentiometer |01. Hencethe same potential is applied across the grid, shunt', and resistor|0811., and operates to modify the spaced potential effects in theVacuum tube VTI. As a result of this, a current displacement occursbetween the anodes of the two tubes, and the space charge is varied inthe vacuum tube VTS, so that ultimately an output current flows from theanode of the vacuum tube VT3 to the winding of the relay MR. If the eggis "good", thev potential difference causes this relay winding to beenergized sufficiently to attract the amature and thus open-circuit theconductors from the transformer winding |39: on the other hand, if theegg is bad, its inherent potential difference is lower, and a sunlcientcurrent does not flow through the relay winding to at tract thearmature, and hence this local circuit 'again permitted to open by thecam 52, so that the plunger is withdrawn by spring 1li. The detainingrocker member 14 cannot regain its former position, however, as it isblocked by a larger diameter of pin 10.

The continued rotation of shaft 2| causes the cam to advance the drum 29by a further step, and then a further egg is tested, etc. This actioncontinues.

It will be noted that the solenoid 11 is displaced angularlycounterclockwise from the position of the lever 85 by a number'of pins10 corresponding to the number of eggs between the position of thislever 86 and the testing station TS. Hence as each egg comes onto thedrum, the corresponding pin 10 is located substantially at the sameradial plane through the axis of shaft 26.

If the'egg has been tested and found satisfactory for hatching, itscorresponding pin 10 has not been changed in position, and hence thisegg in its movement around the drum moves against the pair of pins 35forwardly 'of the aperture in which this egg has been resting, and thenrolls from'these pins onto the discharge trough or channel 8|, andpasses over the inked pad 20| which imprints this egg with suitableindicia, such as Tested and found good, March 16, 1936, and

may be removed to an incubator for hatching.

downward below the door 82, being detained'by.

the pairs of pins 66, so that the eggs do-not fall and break.Ultimately, these unsatisfactory eggs are discharged by the channel 08.

As each egg is either delivered through the opening 02 or carried pastit, the corresponding pin 10 releases the lever 05 so that it can bemoved back for engagement by the succeeding pin 10 for the next egg. Thepins 10 are restored to the inward position by the cam plate 09, and arethen detained by the corresponding detaining rocker 13, as describedabove.

In mycopending application Serial No. 18,251, led April 25, 1935, nowPatent No. 2,102,646 dated December 21, 1937, the fact of inherentpotential differences in eggswas set out, along with results obtained intesting the responses of such eggs. It is preferred in the presentapparatus to have the egg in aroused condition, as by having itsubstantially at the temperature employed for incubation at the normalrate of development (around 100 FJ. The effect of the period ofincubation at such temperature is indicated in the table above. As aresult of actual tests conducted by determining the inherent potentialdifferences of the egg, on the basis of tests with many hundreds ofeggs, it has been found that the present invention can be employed forcorrectly eliminating sterile eggs with an error of less than 5 percent.For example, the average percentage of sterile eggs was 81/2 percent,and the present tests predicted 81A percent sterile, or an error of lessthan 3 percent.

With respect to eggs which are fertile and living when a test is madeafter from'2 to 6 hours incubation, these eggs may be considered inthree groups: 1) eggs which die during incubation on account ofconstitutional Amalformation and weakness apparently respond to the testby being eliminateda condition which is desirable as these eggs willhave developed for a time, but die eventually and do not hatch. (2) Eggswhich are fertile and living at the time of testing but die on accountof unfavorable external circumstances such as breakage, poor techinqueof incubation, lapse of too long a period between laying and setting,etc.,-that is, defects not arising from the actual vitality or lack ofvitality of the particular egg; and also including eggs which are in adying condition at the time the test is made. (3) Fertlle eggs whichhatch, of which substantially all are selected as satisfactory" by thepresent invention, provided that the initial high .resistance of theeggshells has been properly reduced by the preliminary treatment.

The second group of eggs above include those which are in a dyingcondition at the time of test. It has been found that eggs which aredying give an unusually high effect, which may be explained on the basisof the increased metabolism in dying tissues. In general, an egg whichhas died a short time before it is tested will still give the sameindication as a satisfactory egg, which is to be foreseen, as it isknown that the death of an animal does not mean the simultaneous deathof all its organs and tissues. It is possible to test a group of eggs bythe present method, selecting the satisfactory eggs in a first testingoperation as being those which have an inherent potential greater than acertain value; and then to carry the eggs through a second testingoperation in which a higher value than that normal for satisfactory eggsis employed: in this event, the satisfactory eggs will be discharged tothe trough 86, while the eggs which are dying or have recently ded willbe discharged to the trough 8|. It will be understood, therefore, thatthe present invention includes the successive testing of eggs, and oftheir sorting into groups of opposite and low potential for rejects,normal potential for satisfactory eggs, and the higher potentials fordying eggs.

It will be understood that the invention is not limited solely to theconstructions and procedures set out above, but that this may bemodified within many ways within the scope of the appended claims.

I claim:

l. Method of testing eggs, which comprises locally reducng theelectrical resistance between points of the egg which are at differentlevels of height by substantially eliminating the electrical resistanceof the egg shell thereat, and determining `the electromotive forcebetween said points.

2. Method of testing eggs, which comprises wetting the eggs, while warm,at spaced points by a solution of electrolyte, and determining theelectromotive force between said points.

3. Method of testing eggs, which comprises supporting the eggs in adefinite position with the major axis substantially horizontal for atime of about ten seconds to permit the germ to become oriented, wettingvertically spaced points of the egg shell, and determining theelectromotive force between said points.

4. Method of testing eggs prior to the develop-l ment of the embryo,which comprises supporting each egg in a definite position with themajor axis horizontal for a time sulcient for a normal hatchable egg ofthe same period of incubation to orient itself, wetting the egg atvertically spaced points of the egg shell, and determining theelectromotive force between said points.

5. Method of testing and sorting eggs, which comprises supporting theegg in a definite position with the major axis horizontal so that normalhatchable eggs of the same period of incubation may orient themselves,wetting the egg shells at vertically spaced points, determining theelectromotive force between said points, and sorting the eggs intogroups Ahaving similar values of electromotive force.

6. In an apparatus for testing eggs for life activity, an endlessconveyor having means for supporting the eggs in definite position withthe major axis horizontal, means for testing electromotive force andincluding electrodes having contact with the eggs, at least one saidelectrode being movable so that the electrodes may be brought intocontact with the eggs, said testing means also includingdevices forlocally preparing the egg shell prior to testing whereby to avoid theeffect of the normal high resistance of the egg shell, and synchronizingmeans for advancing the conveyor intermittently and for moving saidmovable electrode for contacting the same with the egg 7. An apparatus,as in "claim 6, in which the preparing devices include a movableapplicator for preparing the egg shell for the testing ofthe egg. saidAsynchronizing means being connected for moving the applicator insubstantial unison with the movable electrode.

8. An apparatus for testing eggs, including a conveyor, means forapplying wetting solution at shaft, and means actuated by said shaft forintermittently moving the conveyor and for reciprocating saidreciprocable devices in synchronism with movements of the conveyor.

10. An apparatus of the class described, comprising a conveyor structureincluding'means effective for accomplishing the orientation of the germof each egg so that the egg is positioned according to polarity prior totesting, means for testing electromotive force between vertically spacedpoints of each egg, said conveyor operating to .present eggs insuccession to said testing means, means for sorting the eggs into groupsand including an electromagnetically actuated element, means foramplifying the current effects produced by said electromotive force, andcircuit means connecting said amplifying means and said element so thatthe sorting means is operated in response to the values of electromotiveforce determined by said testing means.

11. An apparatus 'for testing eggs, including testing electrodes forcontacting the eggs and determining the electromotive force thereof, anamplier controlled `by the difference of electromotive potentialsbetween said electrodes, a source of electromotive force and connectionstherefrom to the testing electrodes and including adjustment means sothat accidental currents of the `circuits may be balanced, sorting meansactuated by the amplified current, variable shunt means connected forvarying the response of .the sorting means to a given amplified current,and means for transferring the eggs from the testing electrodes to saidsorting means.

12. Method of testing eggs, which includes positioning each egg with itsmajor axis substantially horizontal for a time suillcient forsubstantial orientation of the germ of the egg, penetrating the eggshell at vertically spaced points by conductive electrodes, anddetermining the electromotive force between said points.

13. An apparatus for sorting eggs, which includes an endless conveyorhaving pairs of pins spaced apart a distance less than the length of anegg, each pair of pins being separated from adjacent pairs by distancesgreater than the minor axis diameter of an egg, said conveyor havingbetween each two pairs of pins a center.

- force.

lifting by pairs of pins as the pins pass toward said horizontal ight,each egg being received in a corresponding said recess while it passesalong the horizontal flight, means for selectively receiving the eggsfrom the belt and pins and operative for sorting the eggs into groups asthe pins pass from the horizontal flight to the return flight, andselector means including upper and lower electrodes and controlled bythe electrical condition of the eggs for determining the actuation ofthe sorting and receiving, means.

14. Method of testing and sorting eggs with respect to the life activitythereof, which comprises positioning each egg with the major axisthereof in a substantially horizontal position, determining the inherentelectromotive force existing between spaced points of each egg, andsorting the eggs into groups having similar values of electromotiveforce.

15. Method of testing and sorting eggs with respect to the l'ifeactivity thereof, which com-- prises warming the eggs to an optimumtemperature of incubation for a period of at least one hour, determiningthe inherent electromotive force of each eg'g, and sorting the eggs intogroups having similar values of electromotive 16. The method of testingeggs for life activity, whichl includes the step of positioning each eggwith the major ,axis thereof in a substan-A tially horizontal position,effecting a reduction of the electrical resistance between spaced pointsof the egg, placing the portion of the egg betweensaid spaced points inan electric circuit including means responsive to voltage on thecircuit, and determining the value of electrical effects arising fromthe egg.

1'7. Apparatus for testing and sorting eggs with respect to the lifeactivity thereof, comprising means for ysupporting an egg with the majoraxis thereof in a substantially horizontal direction, means fordetermining the value of inherent electromotive force of'theeggincluding electrodes for application to points of the egg which areat different levels of height, and means responsive to said determiningmeans for sorting the eggs into groups lhaving similar values ofelectromotive force.

' 18. An apparatus for testing eggs for'life activity, comprising aconveyor having a feeding station and a testing station and means forsupporting the eggs with the major axis horizontal and without movementabout said axis, means for testing electromotive force "includingdevices effective for reducing the electrical resistance oifered by theeggs forpreparing the eggs for such tests and also including electrodesengageable.

with the eggs as they are moved forward by the conveyor, meansassociated with the conveyor for sorting the eggs thereon into groups,said sorting means including preselecting devices actuated in responseto said testing means, and means for driving the conveyor and sortingmeans and preparing devices at a rate suchA that each egg is held on theconveyor with its major axis horizontal for the time suillcient for thegerm of a normal egg to become automatically oriented during themovement from the feeding station to the testing station before the eggis presented for determination by said testing means.

,19. An apparatus for testing essa comprislns a conveyor for receivingand the eggs individually, means for applying wetting solution to spacedpoints on each egg shell, means for testing electromotive force of theeggs individually includng electrodes for contacting the wetted portionsof each egg shall, and means for driving the conveyor at a rate suchthat the germs in the eggs become oriented before the eggs pass fordetermination by said testing means.

20. Apparatus for testing eggs, comprising a conveyor having a feedingstation, a testing station and a sorting station andmeans for supportingthe eggs individually with the major axis horizontal and withoutmovement about said axis, means at the testing station for testingelectromotive force between spaced points at different levels of heightof each egg as presented thereto by the conveyor, means for driving theconveyor at a rate such that each egg is held with its maior axishorizontal for a time suicient for the germ of a normal egg to becomeautomatically oriented during the movement from the feeding station tothe testing station before the egg is presented for determinaon by saidtesting means, and preselecting means at the sorting station controlledby the testing means for sorting the eggs into groups having similarvalues of electromotive force upon arrival of the individual eggs at thesorting station.

y21. Apparatus for testing eggs, comprising a conveyor having a feedingstation and a testing `station and means for supporting the eggs withsented thereto by the conveyor, means for driving the conveyor at a ratesuch that each egg is held with its major axis horizontal for a timesumcient for the germ of a normal egg to become automatically orientedduring the movement from the feeding station to the testing stationbefore the egg is presented for determination by said testing means, andmeans controlled by the testing means for indicating the relativehatchability of the eggs.

22. The method of selecting eggs for hatching purposes, which comprisesmaintaining the eggs at an incubation temperature for a time at leastsumcient to arouse the same, positioning each egg with the major axisthereof in a substantially horizontal position, determining the inherentelectromotiveforce existing between spaced points of each egg, andsorting the eggs into groups having similar values of electromotiveforce,including a group selected for hatching purposes and 'comprisingeggs having. not-less than a predetermined value of electromotiveforce-which is demonstrated by hatchable eggs of like history.

23. The method of selecting eggs for hatching purposes, which comprisesmaintaining the eggs at an incubation temperature for a predeterminedperiod of time, positioning' each egg with the major axis thereof in asubstantially horizontal position. determining the inherentelectromotive force existing between spaced points of each'egg, andsorting the eggs into groups having similar values of electromotiveforce, including a group selected for hatching purposes and comprisingeggs having not less than a predetermined value of electromotive forcewhich is demonstrated by hatchable eggs of like history.

FREDERICK L. RIVENBURJGH.

